This DIY repair and service manual by Haynes, covers 1979-1993 Ford Mustang and Mercury Capri. All models with inline-six, V6 and V8 engines.
Book Excerpt: Ford Mustang 1979-1993, Mercury Capri 1979-1986 Repair Manual
TUNE-UP AND ROUTINE MAINTENANCE
SPARK PLUG REPLACEMENT
COOLING, HEATING AND AIR CONDITIONING SYSTEMS
(Refer to illustrations 30.2, 30.5a, 30.5b, 30.6 and 30.10)
- The spark plugs are located on the side(s) of the engine.
- In most cases, the tools necessary for spark plug replacement include a spark plug socket which fits into a ratchet (spark plug sockets are padded inside to prevent damage to the porcelain insulators on the new plugs and to hold the plugs in the socket during removal and installation), various extensions and a gap gauge to check and adjust the gaps on the new plugs (see illustration).
A special plug wire removal tool is available for separating the wire boots from the spark plugs, but it isn't absolutely necessary. A torque wrench should be used to tighten the new plugs.
- The best approach when replacing the spark plugs is to purchase the new ones in advance, adjust them to the proper gap and replace the plugs one at a time.
When buying the new spark plugs, be sure to obtain the correct type for your particular engine. This information can be found on the Emission Control Information label located under the hood and in the factory owner's manual.
If differences exist between the plug specified on the emissions label and in the owner's manual, assume the emissions label is correct.
- Allow the engine to cool completely before attempting to remove any of the plugs. Some models have aluminum cylinder heads, which can be damaged if the spark plugs are removed when the engine is hot.
While you are waiting for the engine to cool, check the new plugs for defects and adjust the gaps.
BLOWER MOTOR CIRCUIT | ELECTRICAL TESTING
1979 THROUGH 1981 MODELS
- Make sure the battery is fully charged and the fuse is not blown (see Chapter 12). Also check the connections at the blower motor and resistor assembly to be sure they're tight and not corroded.
- Connect the positive lead of a voltmeter to the blower motor electrical connector (orange/black wire) at the blower motor resistor assembly.
- Connect the negative lead of the voltmeter to a good ground (bare metal) on the vehicle frame.
- Place the temperature control lever in the middle of its travel.
- Place the heater function control lever in the Heat position.
- Place the ignition key in the On position.
- Move the blower switch through each of its positions and note the voltage readings. Compare with the Specifications at the front of this Chapter.
If the voltage readings are correct, but the blower motor won't work or doesn't work correctly, either the blower motor or the wiring to the blower motor is faulty.
If there are no voltage readings, and the connections in the circuit are tight and not corroded, the problem is probably in the resistor assembly. Remove the two screws, pull it out of the blower case and check it visually.
- Turn off the key and disconnect the voltmeter. Leave the temperature control and function control levers where they are.
- Disconnect the blower motor electrical connector (orange/black wire) from the resistor assembly terminal.
- Connect the positive lead of an ammeter to the male connector terminal on the resistor assembly.
- Connect the negative lead of the ammeter to the electrical connector. If necessary, insert a male connector terminal into the connector so the ammeter clip will have something to attach to.
Subject: 1979, 1980, 1981, 1982, 1983, 1984, 1985, 1986, 1987, 1988, 1989,1990, 1991, 1992, 1993 Ford Mustang, Mercury Capri service, maintenance, repair. ISBN-10: 1563921308 | ISBN-13: 9781563921308 | Haynes 36050